Summary of Significant Accounting Policies - Computation of Basic and Diluted net loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Net loss	$ (1,202)	$ (852)	$ (1,370)	$ (1,199)	$ (1,237)	$ (1,228)	$ (763)	$ (875)	$ (4,623)	$ (4,103)
Weighted Average Number of Shares Outstanding, Basic	4,520,000	4,460,000	4,445,000	4,434,000	4,432,000	4,431,000	4,420,000	4,417,000	4,465,000	4,425,000
Weighted Average Number Diluted Shares Outstanding Adjustment										0
Weighted Average Number of Shares Outstanding, Diluted	4,520,000	4,460,000	4,445,000	4,434,000	4,432,000	4,431,000	4,420,000	4,417,000	4,465,000	4,425,000
Basic and diluted net loss per share									$ (1.04)	$ (0.93)
Stock Awards Excluded from Computation of Earnings Per Share Amount									981,628	837,035